Basically, there is a shape on the screen and you have to move the cursor along the shape keeping it within the shape boundaries.
You have two small joysticks, similar to those you find on a controller for a radio controlled car / plane etc. You hold these between forefinger and thumb. One joystick controls the cursor up/down movement and the other controls the left/right movement.
As long as you are able to co-ordinate your left hand right hands, as when using an Xbox controller, you'll do ok.
Not much you can do to practice for this one, but it's quite easy as long as you don't rush and don't panic if the cursor drifts out of the lines (and it will).